Furthermore, projection mapping onto a target surface of physical object using one projector generally results in poor coverage of the target surface. Mapping onto target surfaces having a complex shape generally uses multiple projectors from multiple locations in order to cover the entire target surface. Each of these projectors would require an additional video signal, which means that unique rendered content and/or video must be generated for each unique projector. Hence, the cost of rendering/cost of real-time rendering video scales directly with the number of projectors used. So, while many cheaper projectors would be ideal, cost and brightness specifications generally imply use of fewer, brighter projectors.
Additionally, pre-rendered video content would be re-created when the relationship between a projector and the target object changes. Indeed, if the object moves, the pre-rendered video would be recreated for each of the projectors. Hence, when a projector moves, or the object being projected upon moves, the images in the video would need to be rendered again (and/or pre-rendered content would again need to be pre-rendered) to account for the new relative positioning, which makes heavy use of processing resources and further is quite slow. Furthermore, such systems generally require a one-to-one video-to-projector ratio (e.g. “N” videos for “N” projectors).